Air-pump



(No Model.)

B. T. PETTIT.

AIR PUMP. No. 249,085. I Patented Nov. 1,1881.

W ATTORNEYS.

N. PETERS. Mwuw n mr, Waahingtwn. 0:. c.

UNITED STATES PATENT OFFICE.

EDWIN T. PETTIT, OF MARSHALLTOWVN, IONVA.

AIR-PUMP.

SPECIFICATION forming part of Letters Patent No. 249,085, datedNovemberl, 1881.

Application filed May 16, 1881.

To all whom it may concern:

Be it known that I, EDWIN T. PETTIT, ot' Marshalltown, in the county ofMarshall and State of Iowa, have invented a new and useful Improvementin Air-Pumps, of which the following is a specification.

My improvements relate to machines for forcing and compressing air, andhave for their object to furnish a machine by which a continuous streamof air can bet'orced through a pipe or into a receiver.

My invention consistsin acoinpound directacting pump of novelconstruction and arrangement, as hereinafter described and claimed.

In the accompanying drawings, Figure 1 is a plan view of the machine;and Fig. 2 is a vertical longitudinal section on line 0000 of Fig. 1.

Similar letters ofreference indicate corresponding parts.

At opposite ends of a suitable bed-plate, A, there are fixed thecylinders B, which are placed, three at each end, in a horizontal line.These cylinders are closed at their outer ends, so that the inner openends of the cylinders of one set oppose the open ends of the others.

The piston-rods O, three in number, are sustained in hearings onpillow-blocks a, and carry solid plungers b, that are turned smoothly tofit the bore of the cylinders. At their midlength the pistons are formedor fitted with slotted cross-heads c, which are engaged by wrist-pins dof the driving-cranks.

The driving mechanism consists of a shaft, e, sustained on blocks andfitted with disks 9, titted with the crank-pins d for engagement withthe cross-heads ot' the pistons. The pins are placed on radial lines onehundred and (N0 model.)

twenty degrees apart, so that the pistons shall act in succession.

On shaft 6 is a balance-wheel, Z,and acrank 40 or band wheel forconnection of power will be also fitted on the shaft. At the closed endof each cylinder is an outlet-opening, i, beneath which is fitted avalve, h, opening downward. A pipe, it, connects the inlets of each setof pistons, and the two pipes connect with a single discharge-pipe, m,that will lead to the receiver or to the place of use. In operation thepistons are reciprocated by the shaft, and act by their plungers toforce the air in succession from the cylinders. Each piston actscontinuously to force the air from the cylinder at one end or the other,and thus the three pistons insure a strong and steady stream of air tothe receiver.

Having thus fully described my invention, Iclaim as new and desire tosecure by Letters Patent- 1. The combination of two sets of singleactingcylinders, a series of direct-acting piston-rods, with plungersa-t eachend, and ascries of driving-cranks fitted to reciprocate the pistons,substantially as shown and described.

2. The cylinders B,fitted with valves h, connecting-pipes k m,piston-rods O, carrying plungers b, and cross-heads c, andshat'te,p1'ovided with disks 1 and wrist-pins d, substantially as shownand described, combined for operation, as set forth.

EDWIN THOMAS PETIIT.

Witnesses:

HARRISON WEA'rHEaNoX, EDWIN KIMBALL.

